1. Field of the Invention
This invention relates to a roof with a solar battery and is expected to be used as a roof of house. There are provided solar batteries in the roof to generate electric energy.
2. Description of the Related Art
Solar batteries have been used to supply electric power to a house as a part of a roof structure having the solar batteries thereon in order to reduce consumption of energy from conventional sources.
The frame fixing method in which the panel type solar battery unit is secured on an established roof with a dedicated frame, is generally known. It has also been known in the art to arrange so-called solar battery roofing tiles with built-in solar batteries on the roof panel.
There are, however, the following defects associated with the frame fixing method.
First of all, a separate process is required for frame anchoring, and the roofing materials made of roofing tile, roofing board, and rafters are damaged, and it is difficult to obtain a durable watertight structure.
In addition, electrical wires of the solar battery are apt to be influenced by wind, rain, and sun light.
On the other hand, there are the following defects associated with the solar battery roofing tiles.
The electric connections prepared at the joints of the roofing tiles may be damaged by rain-water.
As one modern method of installing the solar batteries on the roof, a roofing technique, in which plural roof panels defining a roof and plural solar battery modules in an associated state, has been developed.
The roof with solar battery provided as a solar battery module allows installation of the solar battery at the same time of installing the roof and provides avoidance of the exposure of the electric wiring and the leakage of rain-water. Thus it avoids the defects in the above-mentioned conventional solar battery installation.
The solar battery module attached to each roof panel is formed with many solar battery cells (solar battery elements) on the surface in a general rectangular thin panel state. Its dimensions are established for fitting the external dimensions of the roof panel on which the solar battery modules are arranged along its length and width.
The required output voltage can be obtained from the roof panel equipped with the appropriate number of solar battery modules.
Namely, the solar battery module provides the designated output voltage according to the solar battery cells formed on the surface of the solar battery module and the solar battery modules on the roof panel are connected in series.
The above roof with solar batteries has the following known disadvantages.
First, when the solar battery itself is excessively heated, energy conversion efficiency tends to drop.
Since the roof easily heats up under illumination by sun light, the solar battery in the roof also cannot avoid being in a high temperature condition.
Consequently, it is difficult to improve the energy conversion efficiency in use.
3. Objects of the Invention
The first object of this invention is to provide the roof with solar battery a way to radiate heat therefrom and to improve energy conversion efficiency.
Second, the joints naturally made between the plural solar battery modules are made watertight.
Thus, the second object of this invention is to provide a roof with solar battery which can be improved in watertightness between each solar battery module.
Third, in using the roof paneled solar battery, the number of the solar batteries on the roof panel is determined by the dimensions of the roof panel, that is, the output voltage of the roof panel is limited, whereby there is a problem of inadequate electrical power supply.
Namely, the electrical power generation by the roof with solar battery is determined by the voltage provided by the dimensions of the roof panel and the number of roof panels connected in parallel. The necessary electrical power is not necessarily always supplied, and the possibility of insufficient electrical power supply cannot be avoided.
Thus, the third object of this invention is to provide a roof with a solar battery which can supply sufficient electrical power.